"But I've still never seen any kind of link that showed brain function or learning capability linked to genetics." This paper says IQ has 70% heritability, bas

"But I've still never seen any kind of link that showed brain function or learning capability linked to genetics." This paper says IQ has 70% heritability, based on a twin adoption study. http://www.ncbi.nlm.nih.gov/pubmed/2218526 http://www.ncbi.nlm.nih.gov/pubmed/2218526 Other twin studies have found 75-90% heritability for attention deficit disorder. Schizophrenia is moderately heritable. Migraine is well-known for running in families.